diff --git a/requirements.txt b/requirements.txt
index 4d15d54..7bc45d5 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,5 +1,5 @@
 cryptography==2.9.2
 lxml==4.9.1
 pyasn1==0.4.5
-signxml==2.6.0
+signxml==4.0.4
 six==1.12.0